U.S. patent number 7,966,404 [Application Number 10/312,080] was granted by the patent office on 2011-06-21 for proxy apparatus and method.
This patent grant is currently assigned to Telefonaktiebolaget L M Ericsson (Publ). Invention is credited to Jan Hedin, Frank Hundscheidt, Stefan Leupers, George Vergopoulos, Jerker Widmark.
United States Patent |
7,966,404 |
Hedin , et al. |
June 21, 2011 |
Proxy apparatus and method
Abstract
A system, comprising various methods and apparatus providing a
transparent communication session setup and control for
communication sessions involving different communication
capabilities, is disclosed. The system receives a request for a
communication session at a proxy apparatus, the request being
originated from a first subscriber to the communication session
using a first group of terminals. The system identifies at least a
second subscriber to the communication session using a second group
of terminals. The system evaluates types of communication being
available for the first group of terminals and at least the second
group of terminals on the basis of the request. The system sets up
terminal sub-sessions from the proxy apparatus to the first group
of terminals and to at least the second group of terminals
according to types of communication being available for the first
group of terminals and at least the second group of terminals.
Inventors: |
Hedin; Jan (Tumba,
SE), Hundscheidt; Frank (Kerkrade, NL),
Vergopoulos; George (Athens, GR), Widmark; Jerker
(Sundbyberg, SE), Leupers; Stefan (Aachen,
DE) |
Assignee: |
Telefonaktiebolaget L M Ericsson
(Publ) (Stockholm, SE)
|
Family
ID: |
8168459 |
Appl.
No.: |
10/312,080 |
Filed: |
April 19, 2001 |
PCT
Filed: |
April 19, 2001 |
PCT No.: |
PCT/EP01/04452 |
371(c)(1),(2),(4) Date: |
November 07, 2003 |
PCT
Pub. No.: |
WO01/82559 |
PCT
Pub. Date: |
November 01, 2001 |
Prior Publication Data
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|
|
|
Document
Identifier |
Publication Date |
|
US 20040073685 A1 |
Apr 15, 2004 |
|
Foreign Application Priority Data
|
|
|
|
|
Apr 20, 2000 [EP] |
|
|
00108043 |
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Current U.S.
Class: |
709/227; 709/204;
709/231 |
Current CPC
Class: |
H04L
65/1069 (20130101); H04L 29/06 (20130101); H04L
69/24 (20130101); H04W 76/20 (20180201); H04L
29/06027 (20130101) |
Current International
Class: |
G06F
15/16 (20060101) |
Field of
Search: |
;709/227 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Caldwell; Andrew
Assistant Examiner: Biagini; Christopher D
Claims
What is claimed is:
1. A method, in a telecommunication network, of providing
simultaneous voice, video and data applications between at least
two subscribers, said method comprising the steps of: receiving, at
a proxy apparatus, a request for a communication session, the
request originating from a first subscriber and identifying at
least a second subscriber to the communication session, the first
subscriber using a first group of terminals and the second
subscriber using a second group of terminals wherein the first
group of terminals have a first set of operating characteristics
and systems and the second group of terminals have a second set of
operating characteristics and systems, the first group of terminals
comprising three terminals including a GSM mobile telephone using a
circuit switched speech bearer, a laptop computer linked via a
PCMCIA card using a circuit switched data bearer to a GSM cellular
communication network and a data terminal connected via GPRS and
the second group of terminals comprising a laptop linked to a
corporate LAN and a telephone using a phone shell running on a
workstation being connected to the corporate LAN; evaluating types
of communication available for the first group of terminals and the
second group of terminals; setting up terminal sub-sessions from
the proxy apparatus to the first group of terminals and to the
second group of terminals according to types of communication
available, wherein the plurality of different terminals in the at
least one of the first group of terminals and the second group of
terminals are each associated with a sub-session of the
communication session, each sub-session being associated with the
communication session; the proxy apparatus mapping incoming media
streams from the first group of terminals onto outgoing media
streams to the second group of terminals and synchronizing
different payload data streams, the data streams including video
and voice.
2. The method according to claim 1, wherein the request for the
communication session identifies the desired types of communication
for the communication session.
3. The method according to claim 1, wherein the evaluating step
further comprises the step of reading from subscriber profiles
communication types of terminal groups used by the subscribers and
corresponding terminal IDs.
4. The method according to claim 1, wherein the evaluating step
further comprises the step of contacting at least one terminal of a
subscriber for input of communication capabilities.
5. The method according to claim 1, wherein the evaluating step
further comprises the step of interrogating the group of terminals
of at least one subscriber to determine related communication
capabilities and readiness for service.
6. The method according to claim 1, wherein the evaluation step
further comprises a the step of negotiating communication
capabilities via a dedicated protocol.
7. The method according to claim 1, further comprising the step of
controlling a transmission of payload or control information
between the proxy apparatus, the first group of terminals of the
first subscriber, and at least the second group of terminals of the
second subscriber, according to the types of communication
available for the terminals.
8. The method according to claim 1, further comprising the step of
controlling the merging of payload information or control
information of at least two terminal sub-sessions for common
transmission via a further terminal sub-session.
9. The method according to claim 1, further comprising the step of
controlling a splitting of payload information or control
information of a terminal sub-session for transmission over
separate terminal sub-sessions.
10. The method according to claim 1, further comprising the step of
controlling a conversion of payload information or control
information.
11. The method according to claim 1, further comprising the steps
of: re-evaluating the types of communication for the group of
terminals of a subscriber after reception of a further request at
the proxy apparatus; and responsive to the re-evaluation result,
changing parameters for at least one existing terminal sub-session,
controlling the release of at least one existing terminal
sub-session, or controlling the setup of at least one new terminal
sub-session.
12. The method according to claim 1, further comprising the steps
of: receiving, at the proxy apparatus, a request to join an ongoing
communication session from a new communication session subscriber;
determining the ongoing communication session corresponding to the
request; evaluating whether the new communication session
subscriber is admitted to the ongoing communication session; and
responsive to the evaluation, rejecting the request to join if the
new communication session subscriber is not admitted to the ongoing
communication session or, if the new communication session
subscriber is admitted to join the ongoing communication session,
evaluating the types of communication available for a group of
terminals used by the new subscriber and setting up at least one
terminal sub-session according to the types of communication
available.
13. The method according to claim 1, wherein the release of at
least one terminal sub-session is achieved by detecting a release
request for at least one terminal sub-session of a communication
session, controlling the release of the at least one terminal
sub-session or changing parameters for the remaining terminal
sub-sessions of the communication session, or controlling the
release of the communication session.
14. The method according to claim 1, further comprising the step of
receiving a request for a communication session from a further
proxy for inter-proxy communication.
15. A proxy apparatus, connected to a gateway in a
telecommunication network and providing simultaneous voice, video
and data streams, the proxy apparatus comprising: a setup control
unit using a processor for receiving a transmitted request for a
communication session, the request originating from a first
subscriber and identifying at least a second subscriber, the first
subscriber using a first group of terminals and the second
subscriber using a second group of terminals, wherein the first
group of terminals have a first set of operating characteristics
and systems and the second group of terminals have a second set of
operating characteristics and systems and each group comprising a
plurality of different terminals, the first group of terminals
comprising three terminals including a GSM mobile telephone using a
circuit switched speech bearer, a laptop computer linked via a
PCMCIA card using a circuit switched data bearer to a GSM cellular
communication network and a data terminal connected via GPRS and
the second group of terminals comprise a laptop linked to a
corporate LAN and a telephone using a phone shell running on a
workstation being connected to the corporate LAN; an evaluation
unit using the processor for evaluating types of communication
transmissions being available for the first group of terminals and
at least the second group of terminals; a mapping unit for mapping
incoming streams from the first group of terminals onto outgoing
streams to the second group of terminals; and a session control
unit using the processor for controlling terminal sub-sessions from
the proxy apparatus to the first group of terminals and to the
second group of terminals according to types of communication
available, wherein the plurality of different terminals in the at
least one of the first group of terminals and the second group of
terminals are each associated with a sub-session of the
communication session, each sub-session being associated with the
communication session, the proxy apparatus achieving
synchronization by coordinating the terminal sub-sessions between
different payload data streams, including video and voice data
streams.
16. The proxy apparatus according to claim 15, wherein the
evaluation unit is adapted to read communication types of terminal
groups and corresponding terminal IDs from a user profile data
base.
17. The proxy apparatus according to claim 15, wherein the
evaluation unit is adapted to contact at least one terminal of a
subscriber for input of communication capabilities.
18. The proxy apparatus according to claim 15, wherein the
evaluation unit is adapted to interrogate the group of terminals of
at least one subscriber to determine related communication
capabilities or readiness for service.
19. The proxy apparatus according to claim 15, wherein the
evaluation unit is adapted to negotiate communication capabilities
via a dedicated protocol.
20. The proxy apparatus according to claim 15, further comprising a
conversion control unit adapted to control a conversion of payload
or control information for transmission between the first group of
terminals of the first subscriber and at least the second group of
terminals of the second subscriber according to the type of
communication for each terminal.
21. The proxy apparatus according to claim 15, further comprising a
merging unit adapted to control the merging of payload information
or control information of at least two terminal sub-sessions for
common transmission via a further terminal sub-session.
22. The proxy apparatus according to claim 15, further comprising a
splitting unit adapted to control splitting payload information or
control information of a terminal sub-session for transmission over
separate terminal sub-sessions.
23. The proxy apparatus according to claim 15, wherein the session
control unit is further adapted to modify parameters of a terminal
sub-session of a communication session subsequent to setting up the
terminal sub-session.
24. The proxy apparatus according to claim 15, wherein the session
control unit is further adapted to control a gatekeeper for address
translation between different terminals.
25. The proxy apparatus according to claim 15, wherein the session
control unit is further adapted to control a gateway or an access
server for transfer of signaling or payload information to related
terminals.
Description
PRIORITY CLAIM
This patent application claims priority to patent application
serial No. PCT/EP01/04452 filed on Apr. 19, 2001.
FIELD OF INVENTION
The present invention relates to a proxy apparatus and method, in
particular to a proxy apparatus and method for simultaneous voice,
video and data applications to users using different terminals.
BACKGROUND OF INVENTION
Telephony and Internet based environments today drive introduction
of IP/IT based services opening virtually unlimited opportunities,
e.g., for multimedia communication services with content access,
application sharing and whiteboarding type of applications. Here,
the difference between existing telecom services will be
significant and attractive for efficient communication.
Already today, different terminals with different capabilities,
e.g., voice, video, data, multimedia, etc. are available in the
market place. These different terminals are operated in different
communication networks, e.g., POTS, ISDN, GSM using network
services like HSCSD and GPRS and also different communication
protocols, e.g., for multimedia the ITU-T H.323 and the IETF
Session Initiated Protocol SIP exist.
However, an increasing number of available services, e.g., voice,
data, multimedia will be provided through a plurality of different
terminals being used for the different communication processes. The
more terminals an end user will use the higher the effort to handle
these different terminals will be. In an extreme case it could be
possible that one end user has to handle a plurality of different
end terminals, e.g., a mobile telephone for a voice call and a
video terminal for video reception during a single communication
session. This situation becomes even more severe in the case two
persons communicating with each other use different groups of end
terminals. Currently no solution is available to facilitate the
handling and interfacing between different communication
capabilities on both sides of a communication link.
These conventional application scenarios are very inconvenient for
subscribers since in a communication session separate call setup is
requested for each type of communication. Subscribers using
different terminals have to initiate a voice communication link at
the beginning of the communication session and to set up data
and/or video links as far as necessary afterwards. However, what is
missing is support for-the coordination of the different setup
procedures and for the control of the communication session. Also,
a subscriber initiating a communication session does not have any
knowledge on what type of terminals the other subscriber will use.
Therefore it is impossible to achieve an efficient communication
session setup and to address multiple terminals using only a single
identifier. In other words, all the burden is put on the
subscribers.
Further, the option to bring new types of applications to GSM,
GPRS, UMTS or Internet users implies the need to introduce a common
control for the different media streams as well as for conversion
between, e.g., speech, data and video in a single circuit or packet
switched bearer. Still further, no approach to overcome problems
like long delays over radio, narrow bandwidth, long network delays,
IP protocol overhead, lack of an efficient mechanism to prioritise
real-time traffic over best effort traffic, etc. exist so far.
SUMMARY OF INVENTION
In view of the above, the object of the invention is to provide a
method and apparatus that allows for a transparent communication
session setup and control for communication sessions involving
different communication capabilities.
According to the present invention this object is achieved through
a proxy method that: receives a request for a communication session
at a proxy apparatus, the request being originated from a first
subscriber to the communication session using a first group of
terminals and identifying at least a second subscriber to the
communication session using a second group of terminals; evaluates
types of communication being available for the first group of
terminals and at least the second group of terminals on the basis
of the request; and sets up terminal sub-sessions from the proxy
apparatus to the first group of terminals and to at least the
second group of terminals according to types of communication being
available for the first group of terminals and at least the second
group of terminals.
Therefore, the present invention relates to a new way to offer
communication services to subscribers using different terminal
groups. Typically, the proxy method according to the present
invention is adapted to receive different media streams, e.g.,
speech, video, and data coming from a first subscriber using a
first group of terminals and to map the incoming media streams onto
outgoing media streams suited to at least a second terminal group
of at least a second subscriber. Clearly, this concept is
independent of either the type of bearer layers used or the
specific communication capabilities of the terminal groups of the
subscribers. Further, according to the present invention it is
proposed to achieve the necessary information exchange to the
subscribers of a communication session using different
sub-communication processes equally referred to as communication
sub-sessions or terminal sub-sessions in short. Each terminal
sub-session is related to a particular communication capability
such as data, voice, video, etc. being support by related
terminals. Setting up terminal sub-sessions to subscribers
according to the types of communication being common or available
to both allows to link the applications of the subscribers using
different terminal groups. One such example would be the mapping of
a multimedia type application to a plurality of end terminals such
as mobile telephones and terminals having data exchange
capabilities. Another advantage of the present invention is that
the number of subscribers to a communication session is not
restricted. Therefore, a communication session may be, e.g.,
initiated between a first and second subscriber. Then a third and
further subscribers may join a pre-installed communication session
to achieve a conferencing type functionality.
According to a preferred embodiment of the invention the request
for the communication session identifies the desired types of
communication. An advantage is that types of communication must not
be determined by the proxy method itself.
According to another preferred embodiment of the present invention
types of communication are determined through reading of subscriber
profiles and related communication types of subscribers from a
subscriber profile data base. This approach is very well suited for
application scenarios where subscribers repeatedly participate in
communication sessions so that it is known in advance which type of
terminal groups will be involved. Due to the availability of
pre-stored user profile data the setup of terminal sub-sessions is
accelerated.
According to another preferred embodiment of the present invention
one subscriber is requested to input the communication capabilities
of her/his terminal group. This approach is advantageous in case a
subscriber to a communication session wants to influence the scope
of services on his own. One typical scenario would be that e.g.,
for cost reasons--a subscriber only wants to use a certain
communication capability type of terminal like voice and avoid,
e.g., video communication that would eventually lead to higher
charges.
According to another embodiment of the present invention terminal
groups of subscribers are interrogated to determine related
communication capabilities and/or readiness for service. Therefore,
if a subscriber is not available at the time being for a certain
application service a provision of this application may still be
delayed until the subscriber hooks onto the communication net later
on. Also, with this approach the selection of services is
determined by availability of terminals of each subscriber.
According to another preferred embodiment of the present invention
communication capabilities are negotiated via a dedicated protocol.
This feature allows to scale for bandwidth and communication costs
and communication performance either from the subscriber side or
from the network operator side. Also, it is possible to flexibly
adapt to a changing load situation in the communication
network.
According to another embodiment of the present invention a
transmission of payload and/or control information between
subscribers is controlled by the proxy apparatus according to the
type of communication of the respective terminal groups. Here, the
question where the actual transmission and/or protocol conversion
of different communication data is implemented is not a
prerequisite for the inventive proxy method and apparatus. In other
words, the proxy method and apparatus only involves the control of
transmission of payload and/or control information. The actual
transmission may be performed in other network nodes, e.g., voice
gateways, access servers, etc. that may already be available.
Therefore, the present invention makes use of already existing
infrastructure.
According to another embodiment of the present invention the
merging of payload information and/or control information is
controlled. Such a merging may either be achieved by multiplexing
or merging into a multimedia stream, e.g., according to the H.323
standard or alternatively through synchronized transmission. Thus,
exchange functionality between a terminal having increased
capabilities and, e.g., a plurality of lower functionality end
terminals may be achieved.
According to another preferred embodiment of the present invention
payload information and/or control information may be splitted.
This aspect allows to extend the previously described merging
aspect into a fully bidirectional exchange of information.
According to another preferred embodiment of the present invention
a conversion of different formats may be executed and/or
controlled. This conversion may either be related to payload
information and/or control information. Again, the present
invention does not require the implementation of the conversion
itself but only requires the control of such a conversion which may
be realised using already installed conversion equipment. E.g., the
aspect of conversion is of importance in case the present invention
is applied to a plurality of bearer layers and/or communication
standards and/or communication protocols.
According to a preferred embodiment of the present invention the
types of communication may be re-evaluated. This reevaluation may
either be carried out on request of a subscriber--e.g., if a
subscriber wants to switch from video to pure voice
communication--or in the case further subscribers join into or drop
out of a communication session. The re-evaluation considers the
fact that the modification of a communication session may require a
new optimisation of related parameters. One such example would be
that if a subscriber using only low bandwidth terminals drops out,
the remaining subscribers of a communication session may then scale
up the used bandwidth or even add further communication
capabilities like data and/or video in addition to the previously
used voice only. Generally, the re-evaluation allows for a time
variant optimised control of an ongoing communication session.
According to a preferred embodiment of the present invention there
is provided the opportunity to handle a request to join a
communication session. This request triggers the determination of
the related ongoing communication session. Then, it is determined
whether the applying subscriber will be admitted to the
communication session or whether the request is to be rejected. In
the case that the new subscriber is admitted new terminal
sub-sessions are established and optionally again the parameters
for the ongoing communication session may optimised. The mapping of
the incoming request to an ongoing communication session may
typically be performed using the target address or an ID for the
communication session which is given in the request. This aspect of
the invention supports the implementation of conference type
communication sessions, however, without the request for each
subscriber to have pre-defined terminal equipment that may incur
high costs. To the contrary, conferencing type communication
sessions may be set up using any type of terminal group in a very
cost-efficient way.
According to a preferred embodiment of the present invention there
is provided the opportunity to release a communication session.
Therefore, either a subscriber may switch off one of his terminals
or completely drop out of a communication session while the
communication session still goes on. Also this aspect of the
present invention supports the flexible time-variant configuration
of the communication session, whatever the demand of the
subscribers will be.
According to another preferred embodiment of the present invention
there is provided the opportunity for inter-proxy communication.
This approach is advantageous in case subscribers are assigned to
different network domains or, in other words, are subscribed to
different networks. Here, one subscriber can be linked to a mobile
cellular communication network of the GSM type and the other to a
cellular mobile communication network of the UMTS type, to a PSTN
network or to an IP-based LAN network. Here, the inventive proxy
method and apparatus is adapted for inter-proxy communication,
which makes it possible to use a common inter-proxy communication
protocol to become independent of network-specific communication
protocols or bearer capabilities.
Further, the objects outlined above are achieved by a proxy
apparatus having: a setup control unit receiving a request for a
communication session, the request being originated from a first
subscriber using a first group of terminals and identifying at
least a second subscriber to the communication session using a
second group of terminals; an evaluation unit evaluating types of
communication being available for the first group of terminals and
at least the second group of terminals on the basis of the request;
and a session control unit setting up terminal sub-sessions from
the proxy apparatus to the first group of terminals and to at least
the second group of terminals according to types of communication
being commonly available for the first group of terminals and is at
least the second group of terminals.
The proxy apparatus according to the present invention achieves the
same advantages as outlined above with respect to the present
invention's proxy method.
Further, a very important aspect of the inventive proxy apparatus
is that it may easily be attached to an existing network without
any additional impacts on the network itself or the end terminals
used therein.
Further, it may be used with a broad range of different, preferably
wireless but also fixed, access technologies, e.g., GSM, GPRS,
EDGE, UMTS, and provide a means for decoupling the one-to-one
relationship between user end terminals and application types.
Further, the inventive proxy apparatus enables the efficient
transfer of multimedia type applications to roaming users of mobile
cellular communication networks. Here, the end user gets a high
quality perception of the application since for each media stream,
e.g., audio, video, data, etc. the proxy controller selects the
native bearer for optimum transmission. Nevertheless, the inventive
proxy apparatus is not only related to mobile communication
standards but may as well co-operate with other multimedia
standards, e.g., H.323 or SIP.
Further, the inventive proxy apparatus hides the network specifics
and enables a service provider and/or network operator to offer
applications initiated in a remote network of any type, e.g., a
fixed network or a LAN or Internet, to roaming, mobile subscribers
thus increasing service provider revenues.
According to another preferred embodiment of the present invention
there is also provided a computer program product directly loadable
into the internal memory of the proxy apparatus comprising software
code portions for performing the inventive proxy method when the
product is run on a processor of the proxy apparatus.
Therefore, the present invention also achieves an implementation of
the inventive method steps on computer or processor systems. In
conclusion, such implementation leads to the provision of computer
program products for use with a 30-computer system or more,
specifically a processor comprised in, e.g., the proxy
apparatus.
The computer program defining the functions of the present
invention can be delivered to a computer/processor in many forms,
including, but not limited to information permanently stored on
non-writable storage media, e.g., read only memory devices such as
ROM or CD ROM discs readable by processors or computer I/O
attachments; information stored on writable storage media, i.e.
floppy discs and harddrives; or information convey to a
computer/processor through communication media such as network
and/or telephone networks via modems or other interface devices. It
should be understood that such media when carrying processor
readable instructions implementing the inventive concept represent
alternate embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, preferred embodiments of the present invention
will be described with reference to the drawings in which:
FIG. 1 shows the provision of a proxy apparatus according to the
present invention between two subscribers with terminals using
different bearer/communication protocols;
FIG. 2 shows the provision of the proxy apparatus according to the
present invention between three subscribers with terminals using
different bearer/communication protocols;
FIG. 3 shows a schematic diagram of the distributed type proxy
apparatus according to the present invention;
FIG. 4 shows a schematic diagram of the integrated type proxy
apparatus according to the present invention;
FIG. 5 shows a schematic diagram of the proxy apparatus controller
according to the present invention as shown in FIGS. 3 and 4,
respectively;
FIG. 6 shows the use of the proxy apparatus according to the
present invention in an inbound mode;
FIG. 7 shows the use of the proxy apparatus according to the
present invention in an outbound mode;
FIG. 8 shows details of a communication session setup according to
the present invention;
FIG. 9 shows further details of an ongoing communication session
according to the present invention in the outbound mode; and
FIG. 10 shows different application scenarios for the proxy
apparatus and method according to the present invention.
DETAILED DESCRIPTION
Throughout the description of the present invention that follows,
reference will be made to the following definitions:
Addressing: In the simplest case provision of a receiver telephone
number, ID or IP address. Alternatively, use of a prefix or any
specific call number to identify a proxy-related communication
request.
Communication session: A logical end-to-end connection between two
or more subscriber terminal groups using one or more
transmission/bearer layers and/or transmission protocols. A
communication session may be supported by one or more communication
systems and divides into at least two or more sub-sessions.
Gateway: A gateway converts payload information and/or control
information between different data formats, protocols and/or
codecs.
Gatekeeper: A gatekeeper handles admission requests, bandwidth
allocation, etc. and forwards messages to the proxy. Also, the
gatekeeper handles address translation, e.g., between E164
addresses and IP addresses.
Multimedia transmission: Transmission of multiple medias using the
same transmission link, technique and/or protocol.
Network access server: Provides a wireless access to a core
network, preferably an IP network.
Protocols: Packet switching protocols, circuit switching protocols,
H.324M (UMTS), H.323, T.120, H.320 (ISDN), etc.
Proxy apparatus/method: Controls communication session, i.e.
subsession(s) set-up, and protocol conversions, performs optionally
also conversion as such.
Subscriber: Person that wants to communicate such that the
communication is based on one or a plurality of terminals. Two or
more subscribers participate in a communication session.
Synchronization: Coordination of different terminal subsessions
that belong to a single communication session. In addition and more
advanced, synchronization--for different terminal sub-sessions may
be executed by investigating time stamps being transmitted from the
corresponding sender, time signals defining a reference time or
synchronization signals.
Terminal: Telecommunication apparatus for transmission and/or
reception having the capability to support one or a plurality of
terminal subsessions of a communication session. Terminals
communicate either explicitly or implicitly with a proxy
apparatus.
Terminal sub-session: Explicit or implicit communication link
between a terminal and a proxy apparatus or any network device,
e.g., a gateway. A terminal sub-session uses a dedicated protocol
and a dedicated transmission mechanism to and/or from the proxy
apparatus or the network device.
Transmission mechanism: ISDN, GSM, GPRS, Ethernet, Satellite, UMTS,
WLAN, IP, HSCSD (high-speed circuit switched data), LAN, PDC,
DAMPS, AMPS, POTS, etc.
Type of communication: Any form of information transmission, e.g.,
speech, audio, video, data or joined multimedia.
Voice gateway: Specific gateway converting speech, e.g., IP-based
signalling and real-time protocol RTP payload into GSM signalling
and speech codecs, e.g., PCM needed by the mobile switching center
MSC.
The present invention is now described in reference to FIGS. 1 and
2. FIG. 1 shows the provision of a proxy apparatus 10 between two
subscribers 12, 14. The proxy apparatus receives a request for a
communication session that originates from the first subscriber 12
using a first group of terminals--e.g., mobile telephone and data
terminal. The request is sent from one terminal of the first group
of terminals, The request identifies the second subscriber 14 using
a second group of terminals--e.g., a multimedia PC. Preferably, the
request comprises a prefix to identify a proxy communication and an
E164 number for a terminal of the second subscriber. Alternatively,
the request is related to an ongoing communication session
identified by a session ID or by a session profile, e.g., "meeting
of all department managers on Monday".
The transfer of a request from one terminal of the first terminal
group to the proxy apparatus is achieved via a first sub-session or
a separate signalling link. Preferably, the proxy apparatus
controls the setup of the further sub-sessions to both terminal
groups. Alternatively, the proxy apparatus controls the setup of
sub-sessions to the terminal group of the second subscriber. This
is possible if already a first sub-session has been established
between the-terminal used by the first subscriber for the transfer
of the request and the proxy apparatus.
The proxy apparatus shown in FIG. 1 evaluates data and speech as
types of communication being available for the first group of
terminals and multimedia as types of communication being available
for the second terminal.
The proxy apparatus then sets up terminal sub-sessions between the
groups of terminals according to types of communication being
available therefore. In the shown scenario with different types of
communication differ between the group of terminals this requires
the merging data and speech into a multimedia data stream for
submission to the second subscriber 14. Also, the reverse direction
the multimedia data stream is split into a single speech and data
information stream for submission to the related terminals. Here,
speech is submitted to the mobile phone and data is submitted to
the PDA.
FIG. 2 shows the provision of a proxy 10 according to the present
invention between three subscribers to another typical
communication session scenario of the present invention. Such a
situation arises, e.g., if a conference type of communication
session is set up right from the beginning or when a communication
session is initialized with two subscribers while the third and/or
further subscribers with a third and/or further group of terminal
join later on.
An important aspect of the invention as shown in FIG. 1 and FIG. 2
is that the setup of a communication session between subscribers is
not static but may vary over time. One reason for this may be that
a subscriber who is already participating in the communication
session enables a further terminal for participation in the
communication session, e.g., by switching it on. Another reason is
that a subscriber disables a terminal in this terminal group, e.g.,
by switching it off, or that the subscriber group of a
communication session changes.
In either case the proxy apparatus will or may re-evaluate the
types of communication for the group of terminals of this
subscriber after reception of a related request. In accordance with
the re-evaluation result the proxy apparatus may, e.g., change of
parameters defining the terminal sub-session characteristics for at
least one existing terminal sub-session. Alternatively, the proxy
apparatus may control the release of at least one existing terminal
sub-session and/or control the setup of at least one new terminal
sub-session in order to optimise the communication session with
respect to the available terminals.
For an extension of the subscribers to a communication session the
proxy apparatus receives a request to join an ongoing communication
session. Then the proxy apparatus determines the corresponding
ongoing communication session and checks whether the new
session-subscriber is admitted to the ongoing communication session
or not. Here, admission to join is checked through interrogation of
subscribers currently participating in the communication session or
through evaluation of a stored user profile or a stored session
profile. If the new subscriber is admitted to join the ongoing
communication session the types of communication for the group of
terminals of the new subscriber are evaluated. if the subscriber is
not admitted, the request is rejected.
In accordance with the evaluation result the proxy apparatus 10
controls the setup of at least one new terminal subsession and
further the information transmission between the terminal groups of
the new subscriber and the existing subscribers. The proxy
apparatus may also change parameters for existing terminal
sub-sessions and achieve the merging and splitting of information,
as already outlined above.
In the case the number of subscribers to a communication session is
reduced--e.g., according to a transition from the application
scenario shown in FIG. 2 to the application scenario shown in FIG.
1--the proxy apparatus receives a release message concerning a
terminal sub-session for the subscriber leaving the communication
session. Further, the proxy apparatus 10 may change parameters for
the remaining terminal sub-session(s) of the communication session
and/or control the release of the complete communication session if
only a single subscriber remains.
In the following, a more detailed explanation of the proxy
apparatus will be given with respect to FIGS. 3 to 5. The
embodiment of the proxy apparatus 10 shown in FIG. 3 uses a minimal
configuration and only controls the communication session as
illustrated above through a controller 16. The controller 16 is
linked to a user profile data base 18 storing communication types
of terminal groups and corresponding terminal IDs for subscribers.
Preferably, the proxy apparatus also stores a list of current
communication session and/or terminal sub-sessions and the status
thereof. In one embodiment this information is stored in the user
profile data base 18. Further, the controller 16 is linked to a
gatekeeper 20 achieving address translation between the first
terminal group and the second terminal group, to a voice gateway 22
for transfer of speech to terminals, and to a network access server
24 for transfer of data to terminals.
According to another embodiment of the proxy apparatus shown in
FIG. 4, the user profile data base 18, the gatekeeper 20, the voice
gateway 22 and/or the network access server 24 are integrated into
the proxy apparatus 10.
It should be noted that the content of the user profile data base
18 may be configured in a flexible way on demand. For mobile
subscribers the entry could be related to the name of the
subscriber and the related number. If a subscriber uses a plurality
of terminals, preferably all addresses or telephone numbers are
stored in relation to the different call types.
According to another embodiment of the present invention the proxy
controller 16 requests from a subscriber via a terminal the desired
communication capabilities through signalling. These communication
capabilities may either be all communication capabilities available
to the subscriber or only a sub-set thereof. Alternatively, the
subscriber may receive a menu of all available communication
capabilities for selection. Further, the proxy controller 16 may
also check for readiness of subscriber terminals to receive
services.
According to another embodiment of the present invention the
controller 16 negotiates communication capabilities--e.g.,
bandwidth or quality of service QoS for a terminal subsession--with
the terminal using dedicated protocols.
As will be noted by those skilled in the art, it depends on the
actual implementation whether either the embodiment according to
FIG. 3 or the embodiment according to FIG. 4 or any suitable
combination thereof will be used for communication-session setup
and control.
Further details of the controller 16 of the proxy apparatus are
shown in FIG. 5. The controller comprises a setup control unit 26,
an evaluation 28, a session control unit 30, a conversion control
unit 32, a merging unit 34 and a splitting unit 36. All units may
be realized in a single hardware and/or software module.
Alternatively, each unit may be realized as a stand-alone hardware
and/or software module. Finally, also any variation between the
possibilities is covered by the present invention.
Operatively, the setup control unit 26 receives the request for a
communication session and supplies it to the evaluation unit 28.
The request for the communication session identifies the desired
type of communication, e.g., data, voice, video, etc. for the
communication session. Alternatively, if no specific communication
capabilities are submitted to the controller 16 it may then have
access to the user profile database 18 to read from subscriber
files communication types used by the subscribers and related
terminals IDs.
Further, the evaluation unit 28 shown in FIG. 5 evaluates the types
of communication being available for the involved group of
terminals on the basis of the request. The request forms the basis
for the evaluation in that it comprises preferred types of
communication which are then analysed for availability. Finally,
the setup control unit 30 controls the setup of terminal
sub-sessions from the proxy apparatus 10 to the terminals according
to the evaluated types of communication being available. Here,
availability means that a terminal handling the corresponding
type(s) of communication is switched on and is reachable and that
further resources to setup a sub-session to the terminal exist.
In more detail, the evaluation unit 28 may communicate with one
terminal of a subscriber for input of communication capabilities.
Also, the evaluation unit 28 is adapted to interrogate terminals to
determine related communication capabilities and/or readiness for
service or to negotiate communication capabilities via a dedicated
protocol.
The conversion control unit 32 of the controller 16 controls
conversion of payload and/or control information for transmission
between the different groups of terminals according to the type of
communication of the terminals.
As shown in FIG. 5, according to a preferred embodiment the proxy
apparatus 10 comprises the merging unit 34 adapted to control the
merging of payload information and/or control information of at
least two terminal sub-sessions for common transmission via a
further terminal sub-session. Also preferably, the controller 16
comprises the splitting unit 36 adapted to control the splitting
payload information and/or control information of a terminal
sub-session for transmission over separate terminal
sub-sessions.
Finally, the session control unit 30 controls and monitors the
operation of the sub-units of the proxy apparatus during a
communication session.
The different-units shown in FIGS. 3 to 5 may alternatively be
implemented either by software or hardware and either by
integrating into existing networking equipment or a standalone
dedicated proxy apparatus. What solution is finally chosen depends
on the actual application and the preferences of the network
operator or service provider offering the proxy functionality.
FIG. 6 and FIG. 7 show application scenarios for the proxy
apparatus 10 explained above. These application scenarios apply to
a first subscriber using a multimedia PC in an IP-based LAN/WAN
environment generating a, e.g., H.323 multimedia data stream. The
first subscriber addresses a second subscriber which uses, e.g., a
terminal having GPRS functionality supporting data, which is
connected to the network via a network access server 22. Also, the
second subscriber uses a mobile telephone having GSM functionality
which is connected to the network via the voice gateway 24, and a
video terminal having GPRS functionality connected to the network
via a video gateway 38.
Further, the first subscriber using the multimedia PC may be linked
to the gatekeeper 20 via a signalling line, e.g., for address
translation between IP addresses and telephone numbers of the
terminals of the second subscriber. As shown in FIG. 6, the payload
is transferred through the proxy apparatus 10 and so that this
scenario is referred to as inbound application scenario.
To the contrary, FIG. 7 shows an outbound scenario for the proxy
apparatus 10. Assuming the same application situation, the
difference is that the multimedia PC is not transferring payload
information to the proxy apparatus 10 itself but directly to, e.g.,
the network access server 22 and the voice gateway 24. Therefore,
in the outbound application scenario the proxy apparatus 10 only
handles signalling information for the control of the communication
set-up and the exchange of payload information during the ongoing
communication session.
In either application scenario shown in FIGS. 6 and 7 the Internet
Protocol may be used as transmission mechanism.
Preferably, also the connections between the proxy apparatus, the
voice gateway 22 and the network access server 24 are based on
IP.
FIG. 8 shows further details for the outbound application scenario
illustrated in FIG. 6. As shown in the upper part of FIG. 8,
initially a request for a communication session set-up is
transferred to the proxy apparatus 10. Alternatively, the request
can be sent via the gatekeeper. The proxy apparatus 10 processes
the request and outputs control instructions to a payload/control
information mapping unit 40 or equivalently to a gateway 40. Once a
control of the set-up is settled the actual transfer of payload
information between the first and second subscriber is
achieved-without inbound activation of the proxy apparatus 10.
Thus, the proxy apparatus 10 is only activated in case further
control is necessary. Further, FIG. 8 also shows that the request
for a communication session may alternatively be submitted directly
to the proxy apparatus 10 bypassing the gateway 40.
As shown in FIG. 9, once a setup of a communication session in the
outbound mode is achieved exchange of information is executed via
the gateway 40. Nevertheless, the proxy apparatus 10 continues to
control the communication session. Optionally, also an exchange of
additional signaling information may be achieved between the
involved subscriber terminals, the proxy apparatus 10, and the
gateway 40, e.g., for an additional menu control of the
communication session.
It should be noted that while above inbound and outbound
application scenarios of the proxy apparatus 10 have been
illustrated, according to the present invention also a combination
of such approaches is applicable, e.g., such that for certain
specific types of payload the inbound solution is chosen and for
the remaining types of payload the outbound solution is chosen. The
actual choice may then depend on available and pre-installed
network infrastructure. E.g., in the case network access servers or
appropriate gateways are already available in the network
additional costs to re-implement the related functionalities again
in the proxy apparatus 10 can be avoided. Here, it is much better
to use resources and provide a proxy apparatus 10 only carrying out
the control of the communication session set-up.
FIG. 10 shows a multiple communication network related application
scenario for the inventive proxy apparatus and method. For the
application scenario shown in FIG. 10 there exist three network
domains, i.e. the GSM cellular mobile communication network, the
UMTS cellular mobile communication network and a corporate LAN
network. Here, a first subscriber is linked to the GSM cellular
communication network and uses a first group of terminals 42. This
group of terminals 42 comprises a standard GSM mobile telephone
using a circuit switched speech bearer, a laptop linked via a
PCMCIA card using a circuit switched data bearer to the GSM
cellular communication network, and a data terminal connected via
GPRS.
As shown in FIG. 10, a second subscriber uses a second group of
terminals 44, a laptop linked, e.g., via WLAN or Bluetooth to the
corporate LAN and a telephone using a phone shell running on a
workstation being connected to the corporated LAN.
As also shown in FIG. 10, a third subscriber is linked to the UMTS
cellular communication network and uses a mobile telephone with
multimedia capabilities 46, e.g., using H.323, H.324M or SIP.
As shown in FIG. 10, the three network domains GSM, UMTS, LAN are
linked to each other using two proxy apparatuses 10-1, 10-2. Here,
the use of several proxy apparatuses 10-1, 10-2 allows to summarize
different calls for transmission over only a single communication
channel using the same transmission protocol, which is preferably
IP.
Further, the proxy apparatuses 10-1, 10-2 shown in FIG. 10 may also
achieve synchronization between different payload data streams,
e.g., video and voice considering the fact that video needs longer
transfer times so that voice is preferably delayed. Another option
would be to use an externally supplied timing reference signal for
synchronization of a plurality of terminals participating in a
communication session.
From the application scenario shown in FIG. 10 it is evident that a
communication session should be considered as a time variant
dynamic process.
Furthermore, it is possible that different subscribers change the
terminals used during the communication session. As outlined above,
this may trigger the re-evaluation of parameters classifying the
related terminal sub-sessions. Another case is that two subscribers
start a communication session and then a third subscriber using his
own terminal group joins the communication session or that a
subscriber enables a further terminal for the communication
session.
In the case of a new joining subscriber there is submitted a
request to join the communication session at the appropriate proxy
apparatuses 10-1, 10-2. The proxy apparatus 10-1, 10-2 determines
whether the subscriber is admitted to join the communication
session or not. In the case of admission the proxy apparatus
evaluates the types of communication for the new subscriber and
carries out at least one of the following steps in compliance with
the evaluation result: Control of the set-up for the terminal group
of the new subscriber and the related terminal sub-sessions,
control of information transmission between the new terminal group
and existing terminal groups, a new optimisation of communication
parameters considering the now existing modified types of
communication for all terminal groups and/or merging/splitting of
information for transmission via a common terminal sub-session or
separate terminal sub-sessions.
To the contrary, for the application shown in FIG. 10 one of a
plurality of subscribers may drop out some or all of his terminals
involved in an ongoing communication session. In this case a
request to release related terminal sub-sessions to the subscriber
or a corresponding release message is received at the proxy
controller 16. In case only two subscribers attend the
communication session this would lead to the release of the
communication session itself.
When a subscriber joins or removes terminals from a communication
session it is a very effective approach to re-evaluate the
parameters determining characteristics of the communication
session, e.g., bandwidth, communication capabilities, etc. This may
lead to a change of parameters and eventually to the release of
existing terminal subsessions which may be substituted through
newly installed terminal sub-sessions according to communication
capabilities which could not be used so far due to restricted
communication capabilities of the removed terminal(s).
As shown in FIG. 10, the proxy apparatus and method according to
the present invention may be applied in different mobile
communication networks, e.g., GSM 900/1800, PCS1900, WCDMA,
CDMA2000, EDGE type of radio networks. The terminals are specified
in view of these standards and no modifications of these terminals
are needed in view of the proxy apparatus and method.
Applications like document editing, electronic whiteboarding, voice
enriched presentations, video conferences are only some examples of
applications relying on the proxy apparatus and method according to
the present invention.
Other applications would be Voice over IP (VOIP) applications or
multimedia applications using, e.g., the H.323 standard. In the
latter case, the proxy apparatus and method takes responsibility to
combine, e.g., the calls from the first terminal group 28 into one
H.323 call towards the corporate LAN and to split the H.323 call
into different calls in the reverse direction.
Therefore, the proxy apparatus 10-1 at the edge of the GSM/GPRS
mobile communication network performs a linkage between multimedia
streams with voice and data into three separate connections towards
the first group of terminals 26. Here, speech and video (usually
both real-time traffic) and data (usually best effort traffic) are
using different bearer layers for their transmission towards the
first group of terminals 26. Each bearer layer in the GSM cellular
mobile communication network is used at its best without
compromising the subscriber's perception of the specific
application.
Appropriate synchronization is provided between the three separate
connections and the multimedia call adding appropriate delays under
control of the proxy apparatus 10-1 to compensate the different
characteristics of the three different GSM speech, GSM data and
GPRS bearer layers.
Further, for the subscribers in the corporate LAN the mobile
subscriber is identified through only a single personal identity
corresponding to a virtual multimedia, e.g., H.323 client
functionality in the proxy apparatus 10-1. In other words, the
particularities of the mobile access are completely hidden through
the proxy apparatus 10-1 enabling seamless communication and
integration for users of standard developed applications.
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